Heat developable light-sensitive materials are known in the photothermographic art. Examples of such heat developable light-sensitive materials and corresponding processes for image formation therein are described in SHASHIN KOGAKU NO KISO (Fundamentals of Photographic Engineering) (published in 1979 by Corona, pp. 553-555), EIZO JOHO (Image Information) (April 1978, page 40), Handbook of Photography and Reprography (edited by Nebletts, 7th Ed., published by Van Nostrand Reinhold Company, pp. 32-33), U.S. Pat. Nos. 3,152,904, 3,301,678, 3,392,020, and 3,457,075, British Patent Nos. 1,131,108 and 1,167,777, and Research Disclosure, No. 17029 (June 1978, pp. 9 to 15).
Many photothermographic processes have been proposed to obtain a color image. Processes for forming a color image by combining an oxide form of a developing agent with a coupler have been proposed. Examples of such a combination of an oxide form of a developing agent and a coupler include the combination of a p-phenylene diamine reducing agent and a phenolic or active methylene coupler, as described in U.S. Pat. No. 3,531,236; a p-aminophenolic reducing agent as described in U.S. Pat. No. 3,761,270; sulfoneamide phenolic reducing agent as described in Belgian Patent No. 802,519 and Research Disclosure, September 1975, pp. 31 to 32; a combination of a sulfoneamide phenolic reducing agent and a four-equivalent coupler, as described in U.S. Pat. No. 4,021,240.
However, these processes are disadvantageous in that since an image of reduced silver and a color image are simultaneously formed in the exposed portion after heat development, the color image becomes turbid.
In order to solve this problem, the silver image may be removed by liquid processing, or a dye alone may be transferred to another layer such as a sheet having an image receiving layer. However, this process is also disadvantageous in that it is very difficult to distinguish between the unreacted matter and the dye and then transfer the dye alone.
These process are further disadvantageous in that development takes a comparatively long period of time, and the resulting image has a high degree of fog and a low color density.
In order to eliminate these defects, an image formation process has been developed utilizing a silver halide in which a mobile dye is formed imagewise and then transferred to a dye fixing layer, as described in Japan Patent Application (OPI) Nos. 149046/83, 154445/84, 165054/84, and 180548/84 (the term "OPI" as used herein means an "unexamined published application"), and U.S. Pat. Nos. 4,503,137, 4,474,867, 4,483,914, and 4,455,363.
Among these types of image formation processes is a process which comprises heating a heat-developable light-sensitive material in the presence of water and a base and/or base precursor. In such a process, heating is normally conducted supplying water to the light-sensitive material.
However, if the light-sensitive material does not absorb water uniformly and rapidly, uneven development takes place, or the total processing time is undesirably the water supplied to the light-sensitive element is distributed to the dye fixing element in a large amount during heat development or dye transfer, the drying time of the dye fixing material becomes longer.